[Case of cystic metastasis of lingual tonsil carcinoma diagnosed first as a branchiogenic cyst].

We report a case of lingual tonsil carcinoma diagnosed first as a branchiogenic cyst. Histopathological findings showed the possibility of a malignant tumor because there was proliferation of the papillary epithelium of the cyst wall. Blind biopsy of the lingual and palatine tonsil was done and the histological findings revealed a cystic metastatic lymph node from a squamous cell carcinoma (SCC) of the lingual tonsil. The diagnosis of the primary unknown cystic metastatic cervieal SCC requires a thorough examination of the palatine or lingual tonsil when there is no evidence of any vestigial remnant of branchiogenic organ.